Just three months after Thumbtack raised $30 million in a round that founder Marco Zappacosta said his startup didn’t need, the services marketplace has raised $100 million more.

Google Capital led the infusion, valuing the five-year-old company at more than $800 million in a round designed to prepare it for an eventual IPO. Existing investors Tiger Global Management, Sequoia Capital and Javelin Venture Partners also participated in the Series D round.

The funding marks the latest in a half-dozen deals Google’s growth-equity venture fund has completed since it formed last year and represents a major turning point for the San Francisco-based startup.

Founded in 2009, Thumbtack aims to make hiring a wedding photographer, landscaper or other professional as easy as buying a book on Amazon.com. It competes against Yelp and Angie’s List as well as venture-backed startups such as Fiverr and HomeAdvisor insofar as it aims to make it easy to find and hire service professionals.

Thumbtack approaches the marketplace a little differently, however, by using many of its 600 or so employees to vet the professionals by checking licenses and curating them for quality. Thumbtack users describe what they need, and then professionals that fit the criterion pay Thumbtack between $3 and $25 to be introduced to each potential customer.

The startup says it is helping more than three million jobs get completed each year, with the average job running around $600.

Zappacosta, who told VentureWire in May that the company still had $12.5 million in the bank, said he wasn’t actively looking for capital. He said after raising the $30 million round from Tiger Global and Sequoia that month, he was bombarded with inbound requests from investors. After giving it some thought he decided there was only one group who could add the expertise he wanted.

So, he contacted Google Capital. He approached Partner David Lawee with a problem Thumbtack was having.

“We had a statistical modeling question and we didn’t know how to answer it or who to hire to solve it,” Zappacosta said. “David connected us to a head a statistician [at Google] who reviewed it and helped us model a forecast. Then he gave us a profile for the type of person we should hire.”

That interaction convinced Zappacosta of the value that would come from having Google Capital as an investor, and it led to investment discussions.

Zappacosta said there was nothing “magical” about the $100 million sum, but said it would be enough to get the company to “the finish line.”

“An IPO is a milestone along the way us and the type of company we want to build,” he said, adding he doesn’t have a date in mind.

Zappacosta declined to say how much, if any, of the recent round would be used to provide liquidity to early shareholders and team members.

The financing increases total outside funding to $150 million. Funds will be used to launch nationwide marketing campaigns, scale the engineering team and continue expanding. The company now operates in more than 700 categories and all 50 U.S. states.